Mechanical ventilation is a treatment method for lung injury, however high tidal volumes exacerbate lung injury. The resolution of wide angle fluorescence microscopy is insufficient for the measurement of precise alveolar dimensions, thus most studies of alveolar mechanics have been carried out in fixed lungs. However, it is impossible to study dynamic alveolar micromechanics in fixed lungs. Confocal microscopy of thin (1-2 micron) sections now enables precise, dynamic tracking of individual alveolar walls in three-dimensions. This investigation aims to (i) quantify heterogeneity of alveolar wall stretch, (ii) correlate alveolar type II cell location, surfactant secretion and calcium signaling with magnitude of wall stretch and (iii) determine the effect of local disease models of non-aerated alveoli on micromechanics in adjacent alveoli.